British intelligence agency Government Communications Headquarters (GCHQ) reportedly used spoofed LinkedIn and Slashdot pages to compromise the computers of network engineers working for global roaming exchange providers based in Europe.

Special teams from GCHQ's My Network Operations Centre (MyNOC) division identified key employees doing network maintenance and security at the targeted companies and determined which of them were users of LinkedIn or Slashdot.org. The teams then directed the targeted individuals to fake versions of those sites which contained malicious code designed to install malware on their computers, German magazine Der Spiegel reported based on secret GCHQ documents leaked by former U.S. National Security Agency (NSA) contractor Edward Snowden.

The technology used for these computer infiltration operations is called "Quantum Insert" and according to past media reports it was also used by the NSA.

GCHQ used this system to target network engineers from Belgian telecommunications provider Belgacom as part of an operation called "Socialist," as well as the employees of "international mobile billing clearinghouses" as part of a separate operation called "Wylekey," Der Spiegel reported.

Services provided by these clearinghouse companies are used by mobile operators to streamline the process of roaming administration and billing, giving those companies access to a large quantity of data about mobile connections.

One of the clearinghouses whose employees were reportedly targeted by GCHQ was Mach, a Luxembourg company that was acquired in July by Syniverse Technologies, a provider of cloud services for mobile carriers and ISPs headquartered in Tampa, Florida. Mach's business in Europe was resold to Starhome of Zurich.

"We acquired the Mach brand, European customer base, and ownership of the Mach clearing software," Guy Reiffer, VP of marketing and partnerships at Starhome and a former Mach employee, said via email. "We have now implemented a brand new Clearing House in Germany and this went live in September 2013. We think it extremely unlikely that our platform is affected by this attack (which was instigated in 2010) but have decided to perform a security audit to ensure that no issues exist."

Syniverse did not immediately respond to a request for comment.

Another clearinghouse reportedly on GCHQ's target list was Comfone of Bern, Switzerland. It did not respond to a request for comment.

In the case of Operation Socialist which targeted Belgacom engineers, the goal was to compromise their computers and then gain access to the GRX (Global Roaming Exchange) routers operated by its BICS subsidiary.

BICS' network includes over 500 direct connections with over 160 countries and is used to route voice and data communications for more than 700 wired and wireless operators worldwide.

Belgacom, whose customers include the European Commission, the European Parliament and the European Council, announced in September that it had discovered sophisticated malware on some of its internal systems. Last month the company also started investigating unauthorized changes made to a router at BICS.

Belgacom did not immediately respond to an inquiry seeking more information in light of the new report that its engineers were targeted using spoofed LinkedIn and Slashdot pages.

The "Quantum Insert" attack technology reportedly used by GCHQ was developed by the NSA and is made possible by partnerships between the intelligence agency and telecommunication companies that operate Internet infrastructure, according to cryptographer and security expert Bruce Schneier.

"As part of the Turmoil system, the NSA places secret servers, codenamed Quantum, at key places on the Internet backbone," Schneier said in a blog post in October. "This placement ensures that they can react faster than other websites can. By exploiting that speed difference, these servers can impersonate a visited website to the target before the legitimate website can respond, thereby tricking the target's browser to visit a FoxAcid server."

FoxAcid is reportedly the codename for servers from which the malicious code injection attacks are launched.

"In the academic literature, these are called 'man-in-the-middle' attacks, and have been known to the commercial and academic security communities," Schneier said. "More specifically, they are examples of 'man-on-the-side' attacks."

"They are hard for any organization other than the NSA to reliably execute, because they require the attacker to have a privileged position on the Internet backbone, and exploit a 'race condition' between the NSA server and the legitimate website," Schneier said.

"We have read the same stories, and want to clarify we have never cooperated with any government agency, nor do we have any knowledge, with regard to these actions, and (to date) have not detected any of the spoofing activity that is being reported," said Darain Faraz, communications manager for the EMEA region at LinkedIn, in an emailed statement. "LinkedIn takes the privacy and security of our members very seriously, and when were made aware of any improper activity, we work to quickly respond."

Dice Holdings, the New York-based company that owns Slashdot.org did not immediately respond to a request for comment.

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